Gearing.



n. B. WEAVER.

GEARING.

N FILED JU Patented A111220, 1915.

. l i inutil,

nonnen1 n wnavnn, or n-E'rn'oim, MICHIGAN, Assrcrnon To 'Tannen-Dammit 'Anm jC(MLUEAMWY, OFDJETROIT, MICHIGAN, -AICORIP0RTIN '0F @HMM T0' all whom it may concern:

Be it known that I, ROBERT B. WEAVER, a citizen of the United States, and'residen't of Detroit, in the county of Wayne and State 'of Michigan, have invented 'certain new and useful improvements 'in Gearing, of whichthe following 'is a specification.

The object of the present invention is to produce a gearing or gear couple, consisting of a pinion having helical teeth and a gear having a circular line of teeth on one of its plane faces of such form-and varrangement as to mesh with the teeth of the helical pinion` when said pinion and gear are so placed that their axes intersect.

In the drawings in which are illustrated a form of my invention, Figure l is a plan view of a gear couple embodying my invention. Fig. 2 is an elevation as seen from the leftrof Fig. 1. Fig. 3 is a plan view on a larger scale of a portion of the line of teeth on the large gear. Figs. 4 and 5 are diagrammatic figures similar to Fig. 2, illustrating the difference in character between the inner and the outer ends of the teeth on the large gear. f

Like reference characters designate the same parts in all the figures of the drawing.

In the drawings a represents a pinion having inclined or helical teeth, and b represents a gear forming the other element of the couple of which the pinion a is one member or element. The gear is a crown gear; that is, its teeth project from one of the faces of the plane disk of which the gear is composed and are all in the same plane perpendicular to the axis of the gear; in other words, this gear is not a bevel gear.

The pinion and geary are arranged so that their axes intersect, as appears'from Fig. 1 where the broken line c, representing the prolongation of the axis of the pinion, is shown as crossing the center of the gear. rllhe pinion a, being a helical pinion, has teeth d, which are yinclined to its axis in the form of sections of helices. The teeth e of the gear, and the spaces f between such teeth, are disposed so as to meshwith the inclined teeth d of the pinion a, and so are not radial to the gear but are inclined to the radii of the gear at the ends of which they are respectively located. The bottoms of the spaces f between the teeth are in the same plane perpendicular to the axis of the gear and their intersection with the Side Specification of Iietters Patent.

Patented npr. 2th, ilwll.

application 'med June x5, ieiaf senaino. 345,03'7.

'a ccircular line concentric with the gear, as the broken circular line shown 'atl g The corners "or :angles between the side and topv faces of the 'teeth are more or lesscurved, the outer eclge or corner h o'f each'ltooth having aconvex 'curvature and the 'opposite ledge or corner z' having a lconcave curvature. The sid'es lof the 'teeth from-bottom to top are approximately straight lines, which l"at the inner end lare 'more steeply inclined vto the plane of the gear thar at the outer end.

Referring to Fig, 4:, whioh shows, the inner ends of a few ofthe teeth of the gear in relation to the corresponding ends of the teeth of the pinion, it will be seen that the side edges 7c of the teeth are inclined at an angle of approximately fifteen de rees to the vertical, while the side edges l o the opposite ends of the teeth make a greater angle with the vertical, which in the present in stance is not far from thirty degrees. rlhe pitch line of the gear is near the inner ends of the teeth e, and on this line the speeds of the pinion and gear are nearly equal, while at the outer ends of the gear teeth, these ends being at the circumference of the gear, the linear speed of the gear is greater than that of the pinion; wherefore greater clearance is required, and the teeth are spread apart with more sloping sides, as clearly shown in Fig. 5. Between the inner and outer ends of the teeth, the sides thereof form warped planes having progressively greater obliquity with respect to the vertical from their inner to their outer ends. A gear couple having the characteristics hereinbefore described is capable of serving uses for which no other gear couple with which I am acquainted is adapted. llt combines the advantages of the crown gear with those of the helical pinion, and allows of the pinion and gear being so placed that their axes are in the same plane and therefore intersect. Such a gearing is very quiet as compared with straight spur gearing and performs its workwith the minimum of friction.

The term vertical as used herein and in the following claims is used in a relative sense, meaning a direction perpendicular to the plane of the gear and parallel to the axis thereof.

Having now described an embodiment of my invention, although without attempting lll@ to illustrate and describe all possible ern- 4 bodiments thereof, or all the modes of itsA use, I declare that what I claim is:

1. A gear couple comprising a pinion and a crown gear arranged with their axes in the same plane and approximately perpendicular to one another, and with their teeth inclined.

2. Gearing comprising a pinion having helically inclined teeth and a Ygear having a circular line of teeth arranged in a plane parallel to the axis of the pinion, such gear being arranged with its axis 'intersecting the axis of the pinion.

Y3. Gearing consisting of a pinion having inclined teeth and a crown gear arranged with its axis in thel same plane with and intersecting the axis of the pinion, and its teeth spirally inclined.

4. A crown gear having teeth so formed that the spaces between the teeth .are approximately strxaight, approm'mately unilstraight from inner to outer ends at their bases and being curved from their inner to their outer ends at the edges of their top faces, the curvature of one edge being con- Vex and of the opposite edge being concave. 'In testimony whereof I have aiiixed my signature, in presence of two witnesses.

ROBERT B. WEAVER. Witnesses LESLIE WILLIAMS,

J. M. READY. 

